Persistent Upper-Extremity Pain after a Car Crash: Case Presentation

A 23-year-old man presents with worsening upper extremity pain. This patient had previously visited the emergency department earlier the same day after being struck by a motor vehicle with resultant fall and left upper extremity pain. Midshaft ulnar and radial fractures (shown) were diagnosed. The fractures had been reduced under sedation and splinted. The patient was awaiting orthopedic evaluation the following morning. It is now 8 hours after that initial presentation. The patient complains of persistent and worsening pain in the extremity, stating that the pain is worse than the actual fracture and that it is now involving his hand. Vital signs are normal and there is no fever.

The splint is taken down and the extremity appears as shown, with swelling and exquisite tenderness along both the dorsal and volar aspects of the forearm. Aside from the noted swelling, the extremity appears relatively normal, with intact capillary refill and radial pulse. Laboratory studies obtained at the time of admission revealed a normal white blood cell count and hemoglobin and hematocrit. The patient appears to be in severe distress. He received multiple doses of narcotic pain medication from the emergency providers. He has extreme pain with active or passive flexion or extension of the wrist or the fingers. He complains of tingling in an ulnar pattern and on the palm of his hand.

Given the location of the fracture (shown) and the worsening symptoms, which of the following complications should be considered at this point?

A. Cellulitis or deep tissue infection
B. Compartment syndrome
C. Arterial insufficiency secondary to vessel laceration
D. None of the above

Answer: B. Compartment syndrome

Compartment syndrome occurs when tissue pressures in a confined anatomical compartment elevate, compromising perfusion and leading to ischemia. As swelling and possibly bleeding into a compartment occur, the pressure exerted on arterial flow through the compartment may impede perfusion and structures passing through; the compartment may thus become ischemic.

Fractures (shown), crush injuries, and trauma resulting in vascular injury are commonly associated with compartment syndrome. Nontraumatic causes include occlusive deep venous thrombosis and ischemia. Constrictive casts, splints, and tight fascial surgical closures may further increase pressure within a compartment.^[1,2]

Compartment syndrome is most likely to occur after injury to which location?

A. Forearm
B. Upper arm
C. Hand
D. Gluteal region

Answer: A. Forearm

Compartment syndrome may occur in any anatomical compartment, but the forearm (shown) and the anterior compartment of the lower leg are most prone to developing it. The extremities have multiple compartments: the upper arm has two compartments (anterior and posterior), the forearm has two (volar and the dorsal), the thigh has three (anterior, medial, and posterior), and the lower leg has four (lateral, superficial posterior, deep, and anterior). Additionally, the hand has four compartments (thenar, hypothenar, central, and interossei).

Trauma is the most common cause of compartment syndrome in the forearm and lower leg. Compartment syndrome is shown here in the forearm of an anticoagulated patient after the radial artery was punctured while obtaining an arterial blood gas.^[3] The diagnosis of compartment syndrome has been based on the classic set of findings of the "P"s: pain (out of proportion and with passive stretch), paresthesia (decreased sensation), paresis, pulselessness, and pallor. Pain is typically the earliest sign of compartment syndrome in the alert and awake patient, noted to be worse with passive stretch of the muscles coursing through the affected compartment.

Skin changes may also include a change in color and darkening of the tissue (shown). A high level of suspicion for compartment syndrome should be maintained in the appropriate clinical setting because the early symptoms may be nonspecific. Sensory deficit typically precedes motor deficit because the nerves passing through the affected compartment are damaged by increasing pressures. Pulselessness and paresthesia are late findings, typically seen after significant damage has already occurred. Large arteries may continue to be patent throughout the course of compartment syndrome.

Commercial kits for compartment pressure measurement are available, such as this device by Stryker. Compartment pressure may also be measured using a 21-gauge needle attached to a typical pressure measurement apparatus, such as that used for measuring central venous pressure or arterial pressure. Measurements should be taken from the site suspected to have the highest level of pressure (usually closest to the fracture or trauma site). Compartment pressures of 20-30 mmHg are thought to be reflective of injury. For compartment pressures >30 mmHg, fasciotomy is generally indicated. The decision to perform fasciotomy is often made on the basis of clinical suspicion.

Fasciotomy is the definitive treatment for compartment syndrome, as performed for this patient after a femur fracture. More conservative approaches to compartment syndrome management are not typically successful. The goal of fasciotomy is to release the tension to affected structures and muscle beds. All compartments (both deep and superficial) suspected of being tense should be released. Care should be taken to avoid damage to other structures such as arteries, nerves, and tendons. Necrotic and ischemic tissue may require debridement; however, some improvement in perfusion may be noted after decompression of the compartment. The skin may be closed 7-14 days later.

If compartment syndrome is left untreated, progressive muscle ischemia ensues. The approximate upper limit of muscle viability is 6 hours following an ischemic insult. However, depending on comorbid conditions and the degree of ischemia, this timeframe may be variable. A Volkmann ischemic contracture may be the end result of an unrecognized or untreated compartment syndrome of the forearm. This results in a permanent flexion contracture of the hand at the wrist, resulting in a claw-like deformity of the hand and fingers (shown). The outcome can be catastrophic, with possible complete loss of the limb or significant loss of extremity function.^[4]

Soon after presentation, this patient's compartment pressures were measured and found to be elevated in both the volar and dorsal forearm (52 mmHg and 34 mmHg, respectively). An emergent volar forearm fasciotomy was performed in the operating room (shown), using a carpal tunnel-type incision that was extended proximally. Upon incision, the forearm muscles appeared pink and healthy. Upon release, the dorsal forearm also became noticeably softer. The patient received aggressive fluid support, empiric antibiotics, and pain control. After 10 days, his incisions were closed. The patient maintained full sensory and motor function of the involved extremity.